One-pot synthesis of surface functionalized spherical silica particles

We present a general and reproducible one-pot synthesis method to prepare spherical silica nanoparticles surface-modified with different functional groups directly from tetraethyl orthosilicate (TEOS). In this study, the surfaces of silica spheres were modified to various degrees of hydrophobicity by organosilanes such as 3-aminopropyltrimethoxysilane (APTMS), 3-isobutyltrimethoxysilane (ITMS) and octyltriethoxysilane (OTES). Scanning electron microscopy (SEM) images revealed that the synthesized particles are uniform and monodisperse. The particles are further characterized using Fourier transform infrared spectroscopy (FTIR), cross-polarized 29Si and 13C MAS NMR spectroscopy, thermogravimetric analysis (TGA) and water contact angle measurements, confirming the successful grafting of surfaces with the respective functional groups.